File



Patented July 23, 1929.

UNITEDISTATIFES I 1,721,822 rarest? OFFICE.

MIOH AL RoIss'oF SPOKANE; WASHINGTON.

FILE;

Application filed May 29, 192s. Serial N6. 281,580.

My present invention relates to improvements in files and is. designedespecially for use on either plane surfaces or curved surfaces. Incertain classesof work as for instance in the repair of automobilebodies, fenders etc, it is frequently necessary to use ,a file havingeither a concave working face or a convex working face, and the primaryobject of my. invention is the provision for means whereby a file may beflexed to bowed shape for the purpose of providing either a convex or aconcave working face.

In carrying out my invention I utilize a steel file that is flexible andresilient so that it may be bowed to provide either a convex or concaveworking face and an extensible frame is provided whereby the fiexure ofthe file blade may be accomplished.

By the utilization. of the device of my invention the flexible resilientfile may with facility and convenience be employed as desired forspecial work, and the tool may be manipulated with facility in theperformance of its functions.

My invention consists in certain novel combinations and arrangements ofparts for accomplishing the above objects as will hereinafter be morefully set forth and claimed.

In the accompanying drawings I have illustrated one complete example ofthe physical embodiment of my invention wherein the parts are combinedand arranged according to the best mode I have so far devised for thepractical application of the principles of my invention. 1

Figure 1 is a view in side elevation showing the file of my inventionprovided with a convex working face. igure2 is a similar view with theworking face of the file changed to concave form. Figure 3 is a faceview of the file blade. Figure 4; is a detail view at the end of thetubular screw bar forming part of the extensible frame. Figure 5 is adetail sectional view showing the manner of securing the file blade toits handle and to a complementary post. Figure 6 is a sectional detailview of the adjusting nut and tubular screw bar, as at line 66, Figure2, together with portion of a rod forming part of the frame.

In Figure 1 I have shown the tool with a convex working face and inFigure 2 the tool is provided with a concave working face. The fileblade 1 is provided with abrading teeth on both of its faces and thisblade as usual is fashioned from steel and is flexible and resilient sothat it may be fashioned with a bowed shape to provide either the convexworking face of Figure 1 or the concave working face of'Figure 2. I

The blade 1 is attached to a handle 2 and to a complementary post 3 atopposite ends of the blade and countersunk :screws 1 are used to securethe blade to the handle and post.

The extensible frame which connects the handle and the post comprises apair of telescopic members one of which as indicated at 5 is a rod thatis pivoted to the handle at 6, the handle being bifurcated or forked toreceive the pivoted end of the rod 5. The telescoping extensible framealso includes atubular screw bar 8 which is pivoted at 9 in thebifurcated handle 10 of the post 3 and this screw bar receives the rod 5as indicated in the drawings.

The tubular screw bar is fashioned with'a tapered end 11 which isslotted at 12 in order that this tapered end may be compressed in toclose frictional contact with the end of the rod 5 which rod is claspedby the split resilient end. Near its tapered resilient split end thetubular screw bar is provided with exterior screw threads 13 with whichan adjusting nut 14 is designed to co-act.

The adjusting nut is preferably round and is fashioned with a circularhead 15 that is knurled to facilitate the turning of the nut. The nuthas an interior threaded bore 16 for co-action with the screw 13 on thetubular screw bar 8. The nut 14L also has a tapered seat or bore 17which conforms to the shape of the tapered resilient split end 11 of thetubular screW bar 8.

From' an inspection of the drawings it will be apparent that by turningthe nut on the screw bar the nut may be run tothe right in Figure 6 sothat its tapered bore will frictionally engage and clamp the splitresilient end 11 of the tubular screw bar on the end of the rod 5. Inadjusting the file, the nut is first loosened so that the rod 5 may beadjusted in the tubular screw bar 8. Thus if the end of the rod 5 ispulled toward the tapered split resilient end of the tubular bar 8, andthen the nut is turned to clamp the tapered resilient end of the screwbar on the rod. The telescopic members 5 and 8 are of proper dimensionsin order to maintain the telescopic relation at all times regardless ofthe manner in which the file blade is bowed or flexed.

Having thus "fully described my invention what I claim as new and desireto secure by dle and post, and a clamp nut for securing,

said members in adjusted position.

2. The combinatlon with a flexlble resilient blade having a handle and apost at opposite ends, of a tubular screw bar pivoted to the post and atelescoping rod pivoted to the handle and a nut on the tubular screw baradapted to clamp the telescoping parts.

3. The combination with aflexible resilient file blade, a handle and apost secured to said blade, of a tubular screw bar pivoted to the postand provided with a tapered resilient free end, a telescoping rodpivoted to the handle and encased within the resilient end of thetubular screw bar, a nut threaded on the tubular screw bar and said nuthaving a tapered interior bore conforming to tapered resilient end ofthe tubular screw bar.

In testimony whereofI affix my signature.

MIOHEAL H. KROISS.

